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Nerd Me: This is a really nice use of this visualization. Human Me: I saw all this stuff in 2016 and Trump still beat the overwhelming odds. (Yes 16% chance of

by atonse 6y ago

Nerd Me: This is a really nice use of this visualization. Human Me: I saw all this stuff in 2016 and Trump still beat the overwhelming odds. (Yes 16% chance of winning is still a chance, I get it... there's just so much deja vu with all these visualizations and articles about his campaign imploding).

protomyth 6y ago
I don't think Trump beat any overwhelming odds. I think the polling was beyond horrible. A bit too many people put too much faith in the NYT and 538's methodology. I wouldn't expect the map to change too much between elections. Now, the 2022 (House & some Senate) and 2024 Presidential will be different because of the change in districting and electoral votes per state caused by the census.
- weakfish 6y ago
  I thought 538 was one of the few outlets to give Trump a decent chance? Granted, I was 16 but I seem to remember that being the case.
  - roywiggins 6y ago
    You remember correctly. "538 thought Clinton had a lock on it" is a meme, but it doesn't seem grounded in anything.
    - jkestner 6y ago
      Perhaps people read 538's odds numbers as poll numbers.
    - bryanlarsen 6y ago
      538 gave Clinton an 86% chance for a brief period of time after the Access Hollywood tapes but before Comey's press conference. I wouldn't call that a lock, but maybe some would.
      - dragonwriter 6y ago
        86% is about a one in seven chance of not happening. It's very much not what anyone would treat as a lock on anything that had important consequences. I grant you plenty of people have sufficient trouble understanding probabilities that they would mistake 86% for a lock, though.
      - roywiggins 6y ago
        Yeah, and then nobody bothered to watch as her chances drifted downward every subsequent day until the election... and they drifted down because the polls changed and the model got more information. It's not really fair to say the model was wrong- it just wasn't clairvoyant. Really, Trump won by a hair's breadth. 538 shouldn't have given him a huge chance to win- he just barely scraped through. It's a genuinely hard problem when the popular vote is very close, since the electoral college throws a huge chaos wrench into everything.,
        bryanlarsen 6y ago
        What should the number have been, then? The final results were essentially a tie with Trump winning the tie breaking coin toss. So 50/50 is right in hind sight. Te systemic error could just have been as easily in Clinton's favour as Trump's, so the number should have been smaller than 50% for Trump. Maybe not as small as 28%, but they weren't far off, IMO.
        gdubs 6y ago
        The model predicts a chance of winning, it doesn’t reflect the final vote percentages. In other words, a win is a win, regardless of whether it’s by a few votes or a landslide. That’s what the 80/20 represented. This is different than the polling averages. Though, electoral vote percentages are captured in 538’s model — they show a spread of possible win scenarios based on many numbers of runs of the model.
        jessaustin 6y ago
        One could imagine such a non-linear model, but one wouldn't consider it well-behaved or even particularly useful for aiding one's understanding of reality.
  - OscarCunningham 6y ago
    You're right. They had him on about 33%, depending on exactly when you look. Interestingly, in 2016 they thought Trump was more likely than the betting markets did. Betfair had him on about 22%. So if they were betting they'd have made a profit. This year the situation has reversed. Betfair has 35% for Trump, whereas 538 has him on only 12%. So they'd be betting on Biden.
    - lastofthemojito 6y ago
      You know what they say, armies go to battle equipped for the last war that they fought. We all take our lessons learned, and recent ones seem to dominate. So yeah, a lot of people seem convinced that since the pre-election polling showed Trump at a disadvantage last time, we'll see an identical surprise victory this time. I personally think that makes as much sense as leaving your umbrella at home on a day with a 75% chance of rain because the last time there was a similar forecast, no rain fell.
  - protomyth 6y ago
    They gave Trump 28.6 which was beyond problematic. You can give baseball analogies but they were wrong. All that bad polling lead into people believing some really dumb things about the election. They've published several articles since then on why the polling is better now. Heck, even their article on being more bullish was tepid. The pre-election article they wrote[1] should have made them actually examine what they were doing. It did not. IDP/TIPP and USC/LA Times got it right. I get that 538 is an HN favorite, but they are too damn politically biased for their own good. 1) https://fivethirtyeight.com/features/how-i-acted-like-a-pundit-and-screwed-up-on-donald-trump/ https://fivethirtyeight.com/features/how-i-acted-like-a-pund...
    - bryanlarsen 6y ago
      Yes, they screwed up the primary, then acknowledged and fixed their mistake. It's a large part of the reason they did much better than everyone else on the election.
    - wtallis 6y ago
      > They gave Trump 28.6 which was beyond problematic. I don't see where you've said anything that comes close to supporting such a strong assertion. 2016 was FiveThirtyEight's third time forecasting a presidential election. Getting one of those three "wrong" when they gave themselves slightly less than one in three chances of getting the 2016 election "wrong" doesn't seem at all surprising. It sounds like you're demanding that FiveThirtyEight make their forecasts deliberately underconfident but still expecting them to call the correct winner every time.
    - weakfish 6y ago
      I do not understand how 28.6% is "problematic," if that's roughly a 1/3 chance. That means, every third election, Trump would win with those odds - far from impossible, and it happened.
    - pwinnski 6y ago
      > They gave Trump 28.6 which was beyond problematic How was that problematic?
  - rsynnott 6y ago
    People _really_ struggle with probabilities (which is why 538's 2020 model page has a cartoon fox to remind them about probabilities, and headlines with visualizations). To a lot of people, saying "there's an 80% chance of THING happening" means "THING will definitely happen".
- burlesona 6y ago
  The NYT I agree with, but Five Thirty Eight specifically called out Trump's chances in the final days before the election: https://fivethirtyeight.com/features/trump-is-just-a-normal-polling-error-behind-clinton/ https://fivethirtyeight.com/features/trump-is-just-a-normal-...
- lastofthemojito 6y ago
  I thought 538 gave Trump a 25% chance to win in 2016? Sure, he wasn't the favorite, but that's like the probability of a typical batter getting a hit in baseball. It isn't what happens in most at-bats, but it shouldn't be a big surprise either.
  - pwinnski 6y ago
    Correct. On Election Day 2016, they had him at 28.6%. https://projects.fivethirtyeight.com/2016-election-forecast/ https://projects.fivethirtyeight.com/2016-election-forecast/
- function_seven 6y ago
  538 analyzed the various polls--and corrected for their methodologies and predictive power--just fine! A sibling comment brings up a batter, and I think that's a great analogy. A good batter has a batting average of, say 0.273. Nobody is shocked when they hit the ball! 538 gave a similar chance to Trump. He hit the ball.
  - rayiner 6y ago
    Yes and no. 538 published an article after the election explaining that there were in fact systemic errors in the models; the result wasn't just random probability within models that were otherwise correct: https://fivethirtyeight.com/features/the-polls-missed-trump-we-asked-pollsters-why/ https://fivethirtyeight.com/features/the-polls-missed-trump-... > While the errors were nationwide, they were spread unevenly. The more whites without college degrees were in a state, the more Trump outperformed his FiveThirtyEight polls-only adjusted polling average,1 suggesting the polls underestimated his support with that group. And the bigger the lead we forecast for Trump, the more he outperformed his polls.2 In the average state won by Trump, the polls missed by an average of 7.4 percentage points (in either direction); in Clinton states, they missed by an average of 3.7 points. It’s typical for polls to miss in states that aren’t close, though. The most important concentration of polling errors was regional: Polls understated Trump’s margin by 4 points or more in a group of Midwestern states that he was expected to mostly lose but mostly won: Iowa, Ohio, Pennsylvania, Michigan, Wisconsin and Minnesota. If the errors had been random rather than systematic, it would have been statistically quite unlikely for Trump to have swept all of those midwestern states.
    - bryanlarsen 6y ago
      AFAICT the polls had a systemic error AND the 538 models included the possibility of a systemic error. It's really the only way that they could have given Trump a 28% chance in the first place. Of course, the polls themselves also acknowledge the chance of a systemic error. They're reported similar to +/- 2% 19 times out of 20. They make no claim that the 19/20 of multiple polls are not correlated.
standardUser 6y ago
He "beat the odds" because most models were incorrect. They have been corrected. Are the models wrong again? Maybe, but it would need to be in a totally different way, and by a much larger margin than in 2016.
- Mountain_Skies 6y ago
  2020 is unprecedented with the various pandemic voting procedures (mail-in, early, and election day) across the country. If the models are wrong this year, that would be much more understandable than them being wrong in 2016.
  - mey 6y ago
    It really is, https://electproject.github.io/Early-Vote-2020G/index.html https://electproject.github.io/Early-Vote-2020G/index.html As of now, the early voting in Texas is 71% of what was voted in Texas in 2016.
- googthrowaway42 6y ago
  > They have been corrected. Based on what are you saying this?
  - standardUser 6y ago
    A lot has been written about this. Here is a good recent article: https://fivethirtyeight.com/features/what-pollsters-have-changed-since-2016-and-what-still-worries-them-about-2020/ https://fivethirtyeight.com/features/what-pollsters-have-cha...
    - sova 6y ago
      Have you ever met a pollster?
      - standardUser 6y ago
        Why don't you skip the theatrics and state your point, if you have one.
rayiner 6y ago
I think Biden will win by a big margin, but I suspect there is a lot more uncertainty baked into the polls than the headline number shows. Polling involves lots of assumptions and making adjustments based on expected turnout of different demographic groups and people with different voter registrations. 95% of people called do not take polls, so it’s not just a truly random sampling like people assume. This year, there are some truly weird things happening. For example, Trump is losing ground along seniors while gaining ground among non-white voters. He is polling 10-20 points better among Hispanic people in Florida, for example, than in 2016. https://fivethirtyeight.com/features/trump-is-losing-ground-with-white-voters-but-gaining-among-black-and-hispanic-americans https://fivethirtyeight.com/features/trump-is-losing-ground-.... Trump is significantly outperforming Romney or McCain among non-whites, and significantly underperforming among seniors. Polls do lots of adjustments based on assumptions about e.g. voter turnout by race, and I don't know if pollsters have really gotten their arms around this situation. The explanation of the "16% chance Trump wins" got a little unscientific in the media last time. To be precise, that's the probability that Trump wins based on the statistical distribution of the different polls and the margins of error within polls. (Roughly speaking, it's "measurement error.") It does not address the possibility that there are systematic methodological shortcomings in the polls. Both things happened in 2016: there was a significant chance of Trump winning anyway, but there was also systemic errors in assumptions regarding low-propensity voters, voters who haven't gone to college, and undecided voters. Pollsters have seemingly fixed those errors, but that doesn't mean there aren't other ones.
- wtallis 6y ago
  > It does not address the possibility that there are systematic methodological shortcomings in the polls. Yes, it does. FiveThirtyEight's modeling includes sources of uncertainty beyond just the margin of sampling error of the individual polls. They've tallied up how much the polling consensus erred for past elections, and have found that while it is not consistent which direction the polling consensus will err for a give election cycle, it is possible to quantify what is a typical size of polling error. Or to put it another way, which methodological shortcomings matter changes from one election to the next, but that doesn't stop you from estimating how big an effect it is likely to have. Assuming that the polls are likely to be collectively wrong by some amount is why the FiveThirtyEight forecast's probability distribution is so wide, with their 80% confidence interval for Trump's electoral college vote total currently spanning roughly 120 to 280. (They also include uncertainty factors for how much the true state of the electorate's opinions could shift between now and election day, but those factors are fading out of the forecast model as election day approaches.)
vmception 6y ago
That's because people have caricatures of each other which are wildly inaccurate. If you talked to people you would understand that what they optimize for is not really related to the caricatures of them, its not the opposite of what "your side" cares about just completely different. When it is obvious that all the news comes from New York City and Los Angeles, and the world resyndicates that, while a large swath of America that actually matters cares about different things, it is easy to tell why the models fail. You would have bet the farm on the undervalued bet on the prediction markets.
- foxhound6 6y ago
  > You would have bet the farm on the undervalued bet on the prediction markets. This is what's frustrating about sites like 538. They have Biden as an 87% chance to win. A betting site I frequent has Biden's winning odds as -180 (1.556 for Europeans). If they really believe the accuracy of their models, they should literally be betting the farm on a Biden win.
  - rsynnott 6y ago
    > If they really believe the accuracy of their models, they should literally be betting the farm on a Biden win. I mean, maybe they are; how would you know? (Though it would seem vaguely improper; not sure about the journalistic ethics take on this but it's at the very least not a great look.) Presumably the money a few 538 employees could bet wouldn't shift the betting markets very much.
  - srtjstjsj 6y ago
    That's not how gambling works. You don't "bet the farm" on a single 87% chance event to win 1.5 farms.
    - gifnamething 6y ago
      That is how betting works when you hedge.
      - 6y ago
tgb 6y ago
I agree with your emotions. 538 puts Biden up only about 6 points in Pennsylvania (their tipping point state). If the race tightens by a few points and the polls are off by a few points, then a very tight race in Pennsylvania is plausible and due to his Electoral College advantage Trump would have a plausible path to victory that doesn't require anything shocking. It just requires several unsurprising things aligning in his favor. The odds are against that, but it's a real possibility that doesn't involve saying that "polls are meaningless!! Fake news!".
- CameronNemo 6y ago
  Of course the supreme court could force PA to throw out ballots at the eleventh hour on election night.
mrtksn 6y ago
Doesn't it mean that having even %16 chance means that it is actually possible? Maybe it's simply not a good idea to analyse this in terms of chances of winning because we will witness just 1 event but the probability says that in 400 years we will have 16 Trump presidencies. It's very counterintuitive, I don't know how to think of it. It's like saying that %99 of StartUps fail but that stat is meaningless to the individual startups(meaningful to govt & investors that will have to deal with 100s or more startups). From subjects perspective, their own startup have %100 chance of success and Trump has %100 chance of winning. Maybe these "chance of winning" statistics should be compiled by examining the roadblocks to the success.
donarb 6y ago
But this visualization has nothing to do with projections or modeling. It's straight numbers, plotting out various pathways for either side to win.
- wtallis 6y ago
  It is based on projections. You can tell because the tree isn't 50 layers deep. They're treating a lot of state outcomes as a foregone conclusion. The description specifically calls out Michigan, Minnesota and Texas as states that aren't really certain, but are treated as such by this visualization.
MeinBlutIstBlau 6y ago
The funny thing is they have Wisconsin (my state) showing biden favored to win. Just look at the electoral college electors record. It's been a red majority since Bush. They even had a swing blue state turned red 2016 that helped cement the state vote. And these were affluent white liberals outside of Milwaukee. This is just going to be 2016 all over again where somehow polling = "the correct prediction" when none it is taking into consideration the voting record of the electoral college. Just a general consensus among a biased selection.
- wtallis 6y ago
  > The funny thing is they have Wisconsin (my state) showing biden favored to win. Just look at the electoral college electors record. It's been a red majority since Bush. Can you clarify what you mean? Wisconsin never went for a Bush, and other than Trump's win in 2016 it's been voting for Democrats in presidential elections since Reagan. What electoral college record and red majority are you referring to? And even if you reject all polling evidence, why is that one Trump win indicative of a solidifying shift toward Republicans, as opposed to expecting a reversion to the mean and Wisconsin going back to being a generally blue state?
titanomachy 6y ago
The fivethirtyeight.com forecast in 2016 gave Trump a 28.6% chance of victory. It's predicting 12% for 2020. That's a pretty big difference. If I told you "there's a 30% chance of rain tomorrow" and it rained, you probably wouldn't accuse me of being wrong (based on that one data point at least).

by atonse 6y ago

protomyth 6y ago

I don't think Trump beat any overwhelming odds. I think the polling was beyond horrible. A bit too many people put too much faith in the NYT and 538's methodology. I wouldn't expect the map to change too much between elections. Now, the 2022 (House & some Senate) and 2024 Presidential will be different because of the change in districting and electoral votes per state caused by the census.

weakfish 6y ago
I thought 538 was one of the few outlets to give Trump a decent chance? Granted, I was 16 but I seem to remember that being the case.
- roywiggins 6y ago
  You remember correctly. "538 thought Clinton had a lock on it" is a meme, but it doesn't seem grounded in anything.
  - jkestner 6y ago
    Perhaps people read 538's odds numbers as poll numbers.
  - bryanlarsen 6y ago
    538 gave Clinton an 86% chance for a brief period of time after the Access Hollywood tapes but before Comey's press conference. I wouldn't call that a lock, but maybe some would.
    - dragonwriter 6y ago
      86% is about a one in seven chance of not happening. It's very much not what anyone would treat as a lock on anything that had important consequences. I grant you plenty of people have sufficient trouble understanding probabilities that they would mistake 86% for a lock, though.
    - roywiggins 6y ago
      Yeah, and then nobody bothered to watch as her chances drifted downward every subsequent day until the election... and they drifted down because the polls changed and the model got more information. It's not really fair to say the model was wrong- it just wasn't clairvoyant. Really, Trump won by a hair's breadth. 538 shouldn't have given him a huge chance to win- he just barely scraped through. It's a genuinely hard problem when the popular vote is very close, since the electoral college throws a huge chaos wrench into everything.,
      - bryanlarsen 6y ago
        What should the number have been, then? The final results were essentially a tie with Trump winning the tie breaking coin toss. So 50/50 is right in hind sight. Te systemic error could just have been as easily in Clinton's favour as Trump's, so the number should have been smaller than 50% for Trump. Maybe not as small as 28%, but they weren't far off, IMO.
        gdubs 6y ago
        The model predicts a chance of winning, it doesn’t reflect the final vote percentages. In other words, a win is a win, regardless of whether it’s by a few votes or a landslide. That’s what the 80/20 represented. This is different than the polling averages. Though, electoral vote percentages are captured in 538’s model — they show a spread of possible win scenarios based on many numbers of runs of the model.
        jessaustin 6y ago
        One could imagine such a non-linear model, but one wouldn't consider it well-behaved or even particularly useful for aiding one's understanding of reality.
- OscarCunningham 6y ago
  You're right. They had him on about 33%, depending on exactly when you look. Interestingly, in 2016 they thought Trump was more likely than the betting markets did. Betfair had him on about 22%. So if they were betting they'd have made a profit. This year the situation has reversed. Betfair has 35% for Trump, whereas 538 has him on only 12%. So they'd be betting on Biden.
  - lastofthemojito 6y ago
    You know what they say, armies go to battle equipped for the last war that they fought. We all take our lessons learned, and recent ones seem to dominate. So yeah, a lot of people seem convinced that since the pre-election polling showed Trump at a disadvantage last time, we'll see an identical surprise victory this time. I personally think that makes as much sense as leaving your umbrella at home on a day with a 75% chance of rain because the last time there was a similar forecast, no rain fell.
- protomyth 6y ago
  They gave Trump 28.6 which was beyond problematic. You can give baseball analogies but they were wrong. All that bad polling lead into people believing some really dumb things about the election. They've published several articles since then on why the polling is better now. Heck, even their article on being more bullish was tepid. The pre-election article they wrote[1] should have made them actually examine what they were doing. It did not. IDP/TIPP and USC/LA Times got it right. I get that 538 is an HN favorite, but they are too damn politically biased for their own good. 1) https://fivethirtyeight.com/features/how-i-acted-like-a-pundit-and-screwed-up-on-donald-trump/ https://fivethirtyeight.com/features/how-i-acted-like-a-pund...
  - bryanlarsen 6y ago
    Yes, they screwed up the primary, then acknowledged and fixed their mistake. It's a large part of the reason they did much better than everyone else on the election.
  - wtallis 6y ago
    > They gave Trump 28.6 which was beyond problematic. I don't see where you've said anything that comes close to supporting such a strong assertion. 2016 was FiveThirtyEight's third time forecasting a presidential election. Getting one of those three "wrong" when they gave themselves slightly less than one in three chances of getting the 2016 election "wrong" doesn't seem at all surprising. It sounds like you're demanding that FiveThirtyEight make their forecasts deliberately underconfident but still expecting them to call the correct winner every time.
  - weakfish 6y ago
    I do not understand how 28.6% is "problematic," if that's roughly a 1/3 chance. That means, every third election, Trump would win with those odds - far from impossible, and it happened.
  - pwinnski 6y ago
    > They gave Trump 28.6 which was beyond problematic How was that problematic?
- rsynnott 6y ago
  People _really_ struggle with probabilities (which is why 538's 2020 model page has a cartoon fox to remind them about probabilities, and headlines with visualizations). To a lot of people, saying "there's an 80% chance of THING happening" means "THING will definitely happen".
burlesona 6y ago
The NYT I agree with, but Five Thirty Eight specifically called out Trump's chances in the final days before the election: https://fivethirtyeight.com/features/trump-is-just-a-normal-polling-error-behind-clinton/ https://fivethirtyeight.com/features/trump-is-just-a-normal-...
lastofthemojito 6y ago
I thought 538 gave Trump a 25% chance to win in 2016? Sure, he wasn't the favorite, but that's like the probability of a typical batter getting a hit in baseball. It isn't what happens in most at-bats, but it shouldn't be a big surprise either.
- pwinnski 6y ago
  Correct. On Election Day 2016, they had him at 28.6%. https://projects.fivethirtyeight.com/2016-election-forecast/ https://projects.fivethirtyeight.com/2016-election-forecast/
function_seven 6y ago
538 analyzed the various polls--and corrected for their methodologies and predictive power--just fine! A sibling comment brings up a batter, and I think that's a great analogy. A good batter has a batting average of, say 0.273. Nobody is shocked when they hit the ball! 538 gave a similar chance to Trump. He hit the ball.
- rayiner 6y ago
  Yes and no. 538 published an article after the election explaining that there were in fact systemic errors in the models; the result wasn't just random probability within models that were otherwise correct: https://fivethirtyeight.com/features/the-polls-missed-trump-we-asked-pollsters-why/ https://fivethirtyeight.com/features/the-polls-missed-trump-... > While the errors were nationwide, they were spread unevenly. The more whites without college degrees were in a state, the more Trump outperformed his FiveThirtyEight polls-only adjusted polling average,1 suggesting the polls underestimated his support with that group. And the bigger the lead we forecast for Trump, the more he outperformed his polls.2 In the average state won by Trump, the polls missed by an average of 7.4 percentage points (in either direction); in Clinton states, they missed by an average of 3.7 points. It’s typical for polls to miss in states that aren’t close, though. The most important concentration of polling errors was regional: Polls understated Trump’s margin by 4 points or more in a group of Midwestern states that he was expected to mostly lose but mostly won: Iowa, Ohio, Pennsylvania, Michigan, Wisconsin and Minnesota. If the errors had been random rather than systematic, it would have been statistically quite unlikely for Trump to have swept all of those midwestern states.
  - bryanlarsen 6y ago
    AFAICT the polls had a systemic error AND the 538 models included the possibility of a systemic error. It's really the only way that they could have given Trump a 28% chance in the first place. Of course, the polls themselves also acknowledge the chance of a systemic error. They're reported similar to +/- 2% 19 times out of 20. They make no claim that the 19/20 of multiple polls are not correlated.

standardUser 6y ago

He "beat the odds" because most models were incorrect. They have been corrected. Are the models wrong again? Maybe, but it would need to be in a totally different way, and by a much larger margin than in 2016.

Mountain_Skies 6y ago
2020 is unprecedented with the various pandemic voting procedures (mail-in, early, and election day) across the country. If the models are wrong this year, that would be much more understandable than them being wrong in 2016.
- mey 6y ago
  It really is, https://electproject.github.io/Early-Vote-2020G/index.html https://electproject.github.io/Early-Vote-2020G/index.html As of now, the early voting in Texas is 71% of what was voted in Texas in 2016.
googthrowaway42 6y ago
> They have been corrected. Based on what are you saying this?
- standardUser 6y ago
  A lot has been written about this. Here is a good recent article: https://fivethirtyeight.com/features/what-pollsters-have-changed-since-2016-and-what-still-worries-them-about-2020/ https://fivethirtyeight.com/features/what-pollsters-have-cha...
  - sova 6y ago
    Have you ever met a pollster?
    - standardUser 6y ago
      Why don't you skip the theatrics and state your point, if you have one.

rayiner 6y ago

I think Biden will win by a big margin, but I suspect there is a lot more uncertainty baked into the polls than the headline number shows. Polling involves lots of assumptions and making adjustments based on expected turnout of different demographic groups and people with different voter registrations. 95% of people called do not take polls, so it’s not just a truly random sampling like people assume. This year, there are some truly weird things happening. For example, Trump is losing ground along seniors while gaining ground among non-white voters. He is polling 10-20 points better among Hispanic people in Florida, for example, than in 2016. https://fivethirtyeight.com/features/trump-is-losing-ground-with-white-voters-but-gaining-among-black-and-hispanic-americans https://fivethirtyeight.com/features/trump-is-losing-ground-.... Trump is significantly outperforming Romney or McCain among non-whites, and significantly underperforming among seniors. Polls do lots of adjustments based on assumptions about e.g. voter turnout by race, and I don't know if pollsters have really gotten their arms around this situation. The explanation of the "16% chance Trump wins" got a little unscientific in the media last time. To be precise, that's the probability that Trump wins based on the statistical distribution of the different polls and the margins of error within polls. (Roughly speaking, it's "measurement error.") It does not address the possibility that there are systematic methodological shortcomings in the polls. Both things happened in 2016: there was a significant chance of Trump winning anyway, but there was also systemic errors in assumptions regarding low-propensity voters, voters who haven't gone to college, and undecided voters. Pollsters have seemingly fixed those errors, but that doesn't mean there aren't other ones.

wtallis 6y ago
> It does not address the possibility that there are systematic methodological shortcomings in the polls. Yes, it does. FiveThirtyEight's modeling includes sources of uncertainty beyond just the margin of sampling error of the individual polls. They've tallied up how much the polling consensus erred for past elections, and have found that while it is not consistent which direction the polling consensus will err for a give election cycle, it is possible to quantify what is a typical size of polling error. Or to put it another way, which methodological shortcomings matter changes from one election to the next, but that doesn't stop you from estimating how big an effect it is likely to have. Assuming that the polls are likely to be collectively wrong by some amount is why the FiveThirtyEight forecast's probability distribution is so wide, with their 80% confidence interval for Trump's electoral college vote total currently spanning roughly 120 to 280. (They also include uncertainty factors for how much the true state of the electorate's opinions could shift between now and election day, but those factors are fading out of the forecast model as election day approaches.)

vmception 6y ago

That's because people have caricatures of each other which are wildly inaccurate. If you talked to people you would understand that what they optimize for is not really related to the caricatures of them, its not the opposite of what "your side" cares about just completely different. When it is obvious that all the news comes from New York City and Los Angeles, and the world resyndicates that, while a large swath of America that actually matters cares about different things, it is easy to tell why the models fail. You would have bet the farm on the undervalued bet on the prediction markets.

foxhound6 6y ago
> You would have bet the farm on the undervalued bet on the prediction markets. This is what's frustrating about sites like 538. They have Biden as an 87% chance to win. A betting site I frequent has Biden's winning odds as -180 (1.556 for Europeans). If they really believe the accuracy of their models, they should literally be betting the farm on a Biden win.
- rsynnott 6y ago
  > If they really believe the accuracy of their models, they should literally be betting the farm on a Biden win. I mean, maybe they are; how would you know? (Though it would seem vaguely improper; not sure about the journalistic ethics take on this but it's at the very least not a great look.) Presumably the money a few 538 employees could bet wouldn't shift the betting markets very much.
- srtjstjsj 6y ago
  That's not how gambling works. You don't "bet the farm" on a single 87% chance event to win 1.5 farms.
  - gifnamething 6y ago
    That is how betting works when you hedge.
    - 6y ago

tgb 6y ago

I agree with your emotions. 538 puts Biden up only about 6 points in Pennsylvania (their tipping point state). If the race tightens by a few points and the polls are off by a few points, then a very tight race in Pennsylvania is plausible and due to his Electoral College advantage Trump would have a plausible path to victory that doesn't require anything shocking. It just requires several unsurprising things aligning in his favor. The odds are against that, but it's a real possibility that doesn't involve saying that "polls are meaningless!! Fake news!".

CameronNemo 6y ago
Of course the supreme court could force PA to throw out ballots at the eleventh hour on election night.

mrtksn 6y ago

Doesn't it mean that having even %16 chance means that it is actually possible? Maybe it's simply not a good idea to analyse this in terms of chances of winning because we will witness just 1 event but the probability says that in 400 years we will have 16 Trump presidencies. It's very counterintuitive, I don't know how to think of it. It's like saying that %99 of StartUps fail but that stat is meaningless to the individual startups(meaningful to govt & investors that will have to deal with 100s or more startups). From subjects perspective, their own startup have %100 chance of success and Trump has %100 chance of winning. Maybe these "chance of winning" statistics should be compiled by examining the roadblocks to the success.

donarb 6y ago

But this visualization has nothing to do with projections or modeling. It's straight numbers, plotting out various pathways for either side to win.

wtallis 6y ago
It is based on projections. You can tell because the tree isn't 50 layers deep. They're treating a lot of state outcomes as a foregone conclusion. The description specifically calls out Michigan, Minnesota and Texas as states that aren't really certain, but are treated as such by this visualization.

MeinBlutIstBlau 6y ago

The funny thing is they have Wisconsin (my state) showing biden favored to win. Just look at the electoral college electors record. It's been a red majority since Bush. They even had a swing blue state turned red 2016 that helped cement the state vote. And these were affluent white liberals outside of Milwaukee. This is just going to be 2016 all over again where somehow polling = "the correct prediction" when none it is taking into consideration the voting record of the electoral college. Just a general consensus among a biased selection.

wtallis 6y ago
> The funny thing is they have Wisconsin (my state) showing biden favored to win. Just look at the electoral college electors record. It's been a red majority since Bush. Can you clarify what you mean? Wisconsin never went for a Bush, and other than Trump's win in 2016 it's been voting for Democrats in presidential elections since Reagan. What electoral college record and red majority are you referring to? And even if you reject all polling evidence, why is that one Trump win indicative of a solidifying shift toward Republicans, as opposed to expecting a reversion to the mean and Wisconsin going back to being a generally blue state?

titanomachy 6y ago

The fivethirtyeight.com forecast in 2016 gave Trump a 28.6% chance of victory. It's predicting 12% for 2020. That's a pretty big difference. If I told you "there's a 30% chance of rain tomorrow" and it rained, you probably wouldn't accuse me of being wrong (based on that one data point at least).